Merck KGaA's $6 billion agreement to acquire Millipore Corp. (NYSE:MIL) may leave investors waiting longer for the "pure value creation" that the company promised about 3 years ago when it bought Serono SA, according to a Bloomberg report, which cited analysts.

Merck will pay $107 per share in cash for Millipore, which is 50% above the closing price on February 19, the last day of trading before the company was reported to have received a takeover bid from Thermo Fisher Scientific (NYSE:TMO).

The deal is expected to give Merck a more profitable business after the company struggled with setbacks on the Erbitux cancer treatment and multiple sclerosis pill.